Device for determining a characteristic point in the cardiac cycle

• US 6,569,103 B2
• Filed: 05/22/2001
• Issued: 05/27/2003
• Est. Priority Date: 12/22/1995
• Status: Expired due to Term

• Current Assignee: Arrow International, LLC (Teleflex Incorporated)
• Original Assignee: Arrow International Investment Corporation (Teleflex Incorporated)
• Inventors: Schreuder, Johannes Jacobus, Hoeksel, Sebastiaan Adrianus Alphonsus Petrus, Jansen, Josef Reinier Cornelus
• Primary Examiner(s): Hindenburg, Max F.
• Assistant Examiner(s): ASTORINO, MICHAEL C
• Application Number:
  US09/863,075
• Publication Number:
  US 20020010402A1
• Time in Patent Office: 735 Days
• Field of Search: 600/300-301, 600/481, 600/485-486, 600/500-515, 128/900, 128/897, 128/898
• US Class Current: 600/481
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/026 Measuring blood flow A61B3/1233, A61B3/1241 take precedence
• CPC Class Codes: A61M 2205/3334 Measuring or controlling the flow rate
• CPC Class Codes: A61M 60/139 inside the aorta, e.g. intra-aortic balloon pumps
• CPC Class Codes: A61M 60/295 Balloon pumps for circulatory assistance
• CPC Class Codes: Y10S 128/90 Blood pressure recorder

Abstract

The present invention relates to a device for determining a characteristic point in the cardiac cycle that comprises means for calculating the curve of the blood flow rate D(t) in the aorta from the curve of the arterial blood pressure signal P(t) and determining from the curve of the blood flow rate D(t) in each cardiac cycle the time at which an incisura point lies. The device can be used for activating an intra-aortal balloon pump (IABP).

Claims

1. A method for determining a characteristic point in the cardiac cycle, said method comprising the steps of:

(a) calculating the curve of the blood flow rate D(t) in the aorta from the curve of the arterial blood pressure signal P(t); and

(b) determining from the curve of the blood flow rate D(t) in each cardiac cycle the time at which an incisura point lies, wherein the incisura point is determined from a first local minimum in the curve of the blood flow rate D(t) after the beginning of an ejection phase.

2. The method according to claim 1, which further comprises delivering a signal when the incisura point is reached.

3. The method according to claim 1, wherein the blood flow rate D(t) lies below a threshold value Dd.

4. The method according to claim 3, wherein Dd is equal to 10% of the blood flow rate when the blood flow rate from the left ventricle has reached its maximum value.

5. The method according to claim 4, wherein Dd=0.

6. The method according to claim 1, wherein the incisura point is determined when D(t)=0 after the beginning of an ejection phase.

7. The method according to claim 2, wherein the signal activates an intra-aortal balloon pump (IABP) to inflate.

8. The method according to claim 1, which further comprises delivering a signal at the beginning of the ejection phase.

9. The method according to claim 8, wherein the signal activates an intra-aortal balloon pump (IABP) to deflate.